Index: modules/overlay/overlay.admin.inc
===================================================================
RCS file: modules/overlay/overlay.admin.inc
diff -N modules/overlay/overlay.admin.inc
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ modules/overlay/overlay.admin.inc	3 Jan 2010 19:12:52 -0000
@@ -0,0 +1,22 @@
+<?php
+//$Id$
+
+/**
+ * @file
+ * Admin page callbacks for the overlay module.
+ */
+
+/**
+ * Form to set overlay options.
+ *
+ * @ingroup forms
+ */
+function overlay_settings_form($form, &$form_state) {
+  // Overlay settings.
+  $form['overlay_user_config'] = array(
+    '#type' => 'checkbox',
+    '#title' => t('Allow users to disable the overlay for their account'),
+    '#default_value' => variable_get('overlay_user_config', 1),
+  );
+  return system_settings_form($form);
+}
\ No newline at end of file
Index: modules/overlay/overlay.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/overlay/overlay.module,v
retrieving revision 1.4
diff -u -p -r1.4 overlay.module
--- modules/overlay/overlay.module	14 Dec 2009 16:36:56 -0000	1.4
+++ modules/overlay/overlay.module	3 Jan 2010 19:12:52 -0000
@@ -30,6 +30,14 @@ function overlay_menu() {
     'access arguments' => array('access overlay'),
     'type' => MENU_CALLBACK,
   );
+  $items['admin/config/system/overlay'] = array(
+    'title' => 'Overlay',
+    'description' => "Settings for the administrative overlay.",
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('overlay_settings_form'),
+    'access arguments' => array('administer site configuration'),
+    'file' => 'overlay.admin.inc', 
+  );
   return $items;
 }
 
@@ -46,6 +54,28 @@ function overlay_permission() {
 }
 
 /**
+ * Implements hook_form_FORM_ID_alter().
+ */
+function overlay_form_user_profile_form_alter(&$form, &$form_state) {
+  if ($form['#user_category'] == 'account') {
+    if (variable_get('overlay_user_config', 1)) {
+      $account = $form['#user'];
+      if (user_access('access overlay', $account)) {
+        $form['account']['overlay'] = array(
+          '#type' => 'checkbox',
+          '#title' => t('Use overlays'),
+          '#default_value' => isset($account->overlay) ? $account->overlay : 1,
+          '#description' => t('Display content creation and administration in overlays.'),
+          '#weight' => 10,
+        );
+      }
+    }
+    return $form;
+  }
+}
+
+
+/**
  * Implements hook_init().
  *
  * Determine whether the current page request is destined to appear in the
@@ -56,9 +86,11 @@ function overlay_permission() {
 function overlay_init() {
   // @todo: custom_theme does not exist anymore.
   global $custom_theme;
+  global $user;
   // Only act if the user has access to administration pages. Other modules can
   // also enable the overlay directly for other uses of the JavaScript.
-  if (user_access('access overlay')) {
+  $user_overlay = (variable_get('overlay_user_config', 1) && isset($user->overlay)) ? $user->overlay : TRUE;
+  if (user_access('access overlay') && $user_overlay) {
     if (isset($_GET['render']) && $_GET['render'] == 'overlay') {
       // If this page shouldn't be rendered here, redirect to the parent.
       if (!path_is_admin($_GET['q'])) {